Signal for concrete mixers



y 21, 1929- G. JAEGER 1,714,475

SIGNAL FOR CONCRETE MIXERS Filed Feb. 4, 1924 2 Sheets-Sheet 1 WmGEBHARD JAEG ER vloavqi'wd Patented May 21, 1929.

UNITED STATES PATENT OFFICE. I

am J'AIGEB, O1 OOLO'MBUS, OHIO, ABSIGNOHTO THE JAEGER IAO'HINE OOH- rm,OI COLUMBUS, OHIO, A CORPORATION OF OHIO.

SIGNAL non conona'rn marinas.

I Application and February 4, 1m. mm Io. mass.

This invention relates more particularly to mixing machines, andespecially concrete mixing machines in which a rotary mixing drum andloader therefor are employed. In 5 the ordinary use of such machines theattendant is relied upon to determine when the materials of the batchhave been sufliciently mixed but his determination is based upon aguess, and therefore not to be relied upon.

1 The object of the present invention is to provide mechanism whereby anannunciator, audible or visual, is actuated to indicate a sufficiency ofthe mixing operation, said mechanism being adapted to be adjusted,within limits, to vary the lapse of time when the annunciator shall beactuated and therefore the number of rotations of the drum to be allowedfor the mixing of the batch.

The invention is embodied in the example herein shown and described, thefeatures of novelty being finally claimed.

In the accompanying drawings- Figure 1 is a view in general sideelevation of a concrete mixer equipped with my invention.

Fig. 2 is a plan view of parts of the machine showing the operatingmechanism in greater detail.

Fig. 3 is a detail on a larger scale showing the cover of the gear box,the mechanism therein being indicated by broken lines.

Fig. 4 is a similar view the said cover being removed and showing themechanism therein in full lines. In this view the signal isdiagrammatically shown.

Fig. 5 is a combined plan and section show ing, on a larger scale thanappears in Fig. 2, the driving means for operating the mechanism in thegear box.

Fig. 6 is a detail mainly in section of a means for insulating the pinon the trigger.

Fig. 7 is a detail illustrating in side view the rear side of the wormgear to which is connected the retracting spring. 45 In the views 11designates the mixing drum of an ordinary form which has an opening at11" for charging it with the concrete materials and discharging themwhen mixed. This drum is mounted to turn on its axis upon a 50 swingingyoke 12 that is journaled in a frame at 12" to permit oscillation of thedrum from charging to discharging position and reversely. To supply thedrum with the sand, gravel and cement it is provided with a loaderbucket 16 pivoted on the forward axle of a truck 30 that travels 1n apair of parallel tracks like that shown at 17 The drum 11 has suitablemeans for turning it on its axis; and the loader bucket 16 has asuitable cable 16 with power for operatlng it to raise it to position todischarge its contents into the drum and to lower it to the ground forits convenient refilling. In a general way the features thus describedor equivalents of them are common to many m xers now sold and it isthought a brlef descrlption of them will sufiice for the purpose ofaiding in explaining the construction and mode of operation of thepresent cooperating elements which are described as follows.

18 designates a box which is mounted on a cross bar of the frame, saidbox having mounted therein a worm gear wheel 19 havmg secured thereon anarm 21 with an in- .clined end 21. Said worm wheel 19 turns loose on abearing 19 fixed to the inner side of the box 18 and secured between itand the gear is a coiled spring 44 tending to turn the wheelanti-clockwise. Hung in the box 18 1s a latch 22 provided with alaterally proectmg pin 23 electrically insulated from the latch ysuitable material as at 23 (see Fi 6). Engaging the worm wheel 19 is asha 24 havmg at one end a worm 24 engaging and operating the wheel 19,and at the other end elongated worm teeth 24 engaged by a worm shaft 26having a pinion 27 engaged by the annular rack 11 of the mixing drum.When the drum is rotated, therefore, the worm gear wheel 19 is turned ifand when the shaft 24 is engaged with it as hereinafter explained. Theshaft 24 carries at its end beyond the worm 24 a block 28 in which areduced end of the shaft 24 turns, said block being bifurcate at itsupper end (see Fig. 5) and having its longer projecting or right handend an upstanding arm 33 from the u per end of which extends fixedlythereto a s aft 34 having a crank arm 35 so that by oscillatin saidcrank arm the rod 32 can be shifted ingltudinally. On the end member ofa yoke 36 fixed on the loader bucket is a laterally projecting pin 36that, when the loader is raised to drum-charging osition, strikes thecrank arm 35 and shifts t e rod 32 to the left (see Fig. 1). lVithin thebox the rod 32 is provided with a cam member 37 that strikes a truncatedcorner of the block 28 and raises that member and the shaft 24 if theybe down (see broken lines Fig. 3). The cam member is of such a form thatwhen the shaft 25 has been lowered to release the worm from the gearwheel the block 28 is of such form that it rests on the member with thecross pin 29 in position to abuttingly receive the blunt end of the hookof the latch 22. When pressure of the pin 36 is removed from crank-arm35 by the lowering of the loader bucket a spring 38 between the righthand end of the box 18 and a washer and stop on the rod 32 tends torestore the crank-arm 35 to position for reoperation by the raising ofthe loader bucket.

In order to predetermine the number of rotations to be made by themixing drum before the giving of the signal the cover of the box is madewith an arcuate slot 18 concentric with the axis of the worm gear wheel19 and in said slot is a stop pin 40 adapted to be clampingly secured toa rotary disk 45 having a pointer 46 at any point in the slot by meansof a set screw 41, said slot pin when fixed adapted to arrest theanti-clockwise movement of the arm 21 under the influence of the wormgear spring at the selected starting position and thereby control thedegree of the clockwise swing of said arm. The pointer 46 of disk 45cooperates with a scale suitably marked with divisions and numbers 5,10, 15, 20 and 25 indicating the number of rotations to be made whensaid pointer is set opposite thereto or opposite a division mark betweenthem.

There is illustrated. in the example shown an electrically operated horn50, such as used on automobiles, the wiring of which is connected to thepin 23, any source of electricity at 51, and ground at the box 18.Normally the circuit of the horn is open but when the inclined end 21 ofthe arm 21 strikes the pin 23 the circuit is closed and the horn soundedas usual in such devices. The clockwise swin of the arm 21 also releasesthe block 28 rom the hook 22 said block together with the shaft 24dropping to the position shown in Fig. 3 with the blunt end of the hookabutting against the pin 29. If desired a manually operated switch 52can be inserted as indicated in the circuit to insure an open circuit(see Fig. 4) when the machine is not in use. a

The operation which or n be readily gathered from what has been said isbriefly this: During the operation of the machine loader are, in thevariety of mixer shown,

manually controlled for obvious reasons.

Assuming that the drum has just been an plied with the concretematerials and t e loader retracted, the Worm 24* engaged with the Wormwheel 19 and the arm 21 retracted to lie against the stop 40 in thearcuate slot the rotation of the drum causes the arm 21 to turnclockwise slowly to position to strike with its end 21 the pin 23 andrelease the block 28 which falls to position shown by broken lines Fig.3 as before stated. In this position the circuit of the horn 50 isclosed through the block 28 and shaft 24: and the I horn sounded. Theshaftv 24 then turns idly. Because the worm gear 19 is relieved ofoperation by the worm 24 the spring 44 restores the arm 22 to startingposition. The parts remain in this last described osition while the drumis oscillated to the le t to discharge it and returned to chargingposition after which the loaderis raised to rechar e the mixing drumwhich raising actuates t e rod 32 to reset the block 28 and the shaft 24b means of'the cam 37 .thereon as before state The forms of the partscan be varied without departing from the gist of the invention claimedand combinations of parts fewer than the whole number of them may beused. I

What I claim is:

1. In an instrument of the class described, an electric signallingmeans, a laterally movable worm shaft, means for continuously rotatingthe worm shaft in one direction, a rotary worm gear, means for holdingthe worm shaft in engagement with the worm gear to operate the latter,said worm gear carrying a circuit closer for causing the actuation 0said signalling means after a predetermined number of revolutions of theworm shaft, means for releasing the worm shaft from the worm gear duringthe actuation of the signal, means for retracting the worm gear to astarting position and means for automatically restoring said worm shaftto operating engagement with said worm gear.

2. Means for use in connection with a rotary mixing drum and a loadertherefor consisting of a laterally movable worm shaft adapted to berotated by the drum, a worm gear engaged by the worm shaft, a latch forsustaining said worm shaft in operating engagement with the worm gear,means for causing the releaseof the worm shaft laterally from engagementwith the worm gear after a predetermined number of revolutions of themixing drum, and means operated by the loader for effecting thereengagement of the worm shaft with the worm when the loader is raisedto charging position.-

3. Means for use in connection with a sustaining said worm shaft inoperating engagement with the worm gear, means for causing the releaseof the worm shaft laterally from engagement with the worm gear after apredetermined number of revolutions of the mixing drum, means forretracting the Worm to a starting position, and means operated by theloader for efiecting the reengagement of the worm shaft with the wormwhen the loader is raised to charging position.

GEBHARD J AEGER.

